British scientists have discovered the world's oldest fossilized vomit, believed to have come from a large marine reptile 160 million years ago. The vomit contains the remains of dozens of belemnites-squid-like shellfish that lived in abundance in the seas around what is now Britain. Belemnites were eaten in great numbers by ichthyosaurs, large marine reptiles similar in size and shape to dolphins but with pointed snouts full of sharp teeth. The vomit fossil was discovered in a clay quarry in Peterborough by Professor Peter Doyle, from Greenwich University, and Jason Wood of the Open University. Having eaten dozens of belemnites, an ichthyosaur would regurgitate their indigestible bullet-shaped shells in much the same way that an owl does after eating a mouse whole. It is these shells that have been discovered in the fossil vomit. "We believe that this is the first time the existence of fossil vomit on a grand scale has been proven beyond reasonable doubt," said geologist Professor Doyle. "The Peterborough belemnite shells, viewed under a powerful scanning electron microscope, have revealed 'acid etching' marks caused by digestive fluids from the gut of a marine reptile, proving that the belemnites had been eaten by a predator. The fact that most of these belemnites were juveniles reinforces our view that they did not die of old age." It was highly unlikely that the shells passed through the ichthyosaurs intestines and were excreted as droppings, as they would have damaged the soft tissue of the reptile's internal organs," Doyle said. "The only alternative is that the shells were vomited out, in much the same way that modern-day sperm whales regurgitate the indigestible beaks of squid they have eaten." The large concentration of belemnite fossils in the Peterborough clay quarry suggests that 160 million years ago the area was a shallow-water, coastal feeding ground for belemnites. The abundant shellfish attracted the ichthyosaurs that ate them ! Photograph of a belemnite
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